The danger associated with sending or receiving text messages (SMS, MMS), or voice calls while driving is well known and documented and against the law in most states.
Many studies show that while legally intoxicated person traveling at 70 mph applies brakes on average 4 feet beyond the baseline, a sober person receiving text message applies brakes on average 36 feet beyond the baseline, and while sending text message, on average 70 feet beyond the baseline.
According to National Transport Safety Board (NTSB) statistic, in year 2011, more than 3000 lives was lost in US due to the accidents caused by drivers distracted with sending or receiving text messages, or engaged in phone conversation while driving. Also several deadly train accidents were accredited to the fact that the train operator was actively involved in SMS transmission prior to the accident.
However, regardless of those statistics, 66% of the respondents of 2007 Harris Interactive poll admitted that they text while driving. Those numbers are even higher among the youngest drivers who already are higher in their share of road accidents. As such, method for automatic detection that the user of the mobile terminal is in a moving vehicle not equipped with the hands-free device while performing the function of a driver may save many thousands of lives.